Driveable catheter system

ABSTRACT

The system ( 2 ) includes a catheter drive unit ( 22 ) and a catheter ( 24 ) extending therefrom movably mounted to a catheter drive sled ( 26 ). The catheter drive unit rotates and translates the catheter core ( 34 ) within the catheter sheath ( 36 ). The sled has a serrated, conical drive unit interface ( 82 ), with a bag-piercing tip ( 86 ) mateable with a translator drive ouput ( 92 ) so that a sterile drape ( 112 ) enclosing the catheter drive unit is automatically pierced when the catheter drive unit is mounted to the sled. A control unit ( 6 ) is spaced apart from the catheter drive unit and provides power and commands to the catheter drive unit and receives information and data from the catheter drive unit. The rotator and translator drive motors ( 54, 90 ) are operated from both the control unit and the catheter drive unit. Both the control unit and catheter drive unit have translation displacement displays ( 10, 30 ).

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a Continuation of U.S. patent application Ser. No. 09/317,778,filed on May 24, 1999, now U.S. Pat. No. 6,398,755, and is aContinuation-in-part of U.S. patent application Ser. No. 09/167,178,filed Oct. 6, 1998, entitled “Driveable Catheter System”, now abandonedthe disclosure of which is incorporated by reference. This is alsorelated to U.S. patent application Ser. No. 09/130,198, filed Aug. 5,1998, entitled “Automatic/Manual Longitudinal Position Translator andRotary Drive System for Catheters”; U.S. patent application Ser. No.09/047,064, filed May 7, 1998, entitled “Combined Motor Drive andAutomatic Longitudinal Position Translator for Ultrasonic ImagingSystem”; U.S. patent application Ser. No. 08/721,433 filed Sep. 27,1996, entitled “Catheter System and Drive Assembly Thereof”; U.S. patentapplication Ser. No. 08/722,325 filed Sep. 27, 1996, entitled “Devicefor Controlled Longitudinal Movement of an Operative Element Within aCatheter Sheath and Method”; and U.S. Pat. No. 5,361,768, issued Nov. 8,1994, entitled “Automated Longitudinal Position Translator forUltrasonic Positioning Probes, and Method of Using Same”.

BACKGROUND OF THE INVENTION

The present invention relates generally to catheters systems. Inparticular, the present invention is directed to a catheter system thatprovides for the controlled longitudinal movement of an elongateelement—such as a rotatable catheter core with an operative element, forexample an ultrasonic transducer or an optical fiber imaging device, atits distal end, or a drive cable with an atherectomy cutter at itsdistal end—housed within a sheath positioned within a patient.

Arteriosclerosis, also known as atherosclerosis, is a common humanailment arising from the deposition of fatty-like substances, referredto as atheromas or plaque, on the walls of blood vessels. Such depositsoccur in both peripheral blood vessels which feed the limbs of the bodyand the coronary vessels which feed the heart. When the depositsaccumulate in localized regions of a blood vessel, stenosis, ornarrowing of the vascular channel, occurs. Blood flow is restricted andthe person's health is at serious risk.

Numerous approaches for reducing and removing such vascular depositshave been proposed, including balloon angioplasty where a balloon-tippedcatheter is used to dilate a region of atheroma, and other devices thatare pushed or pulled along or through a deposit, such as atherectomywhere a blade or cutting bit is used to sever and remove the atheroma,spark gap reduction in which an electrical spark bums through theplaque, laser angioplasty where laser energy is used to ablate at leasta portion of the atheroma, and opening of vessels through the use ofstents.

Two major difficulties in using such devices are maintaining a constanttranslational rate for the device and obtaining images of andinformation on the region of the blood vessel to be treated. Severalimaging techniques have been proposed. Catheters incorporatingmechanical rotation of ultrasonic transducers for imaging are disclosedin U.S. Pat. Nos. 4,794,931; 5,000,185; 5,049,130; and 5,024,234. Thesecatheters scan in a plane normal to the catheter axis. Cathetersemploying phased array imaging systems are disclosed in U.S. Pat. Nos.4,841,977 and 4,917,097. Catheters employing fiber optic imagingcomponents are also known.

Generally deposits extend some longitudinal distance along the length ofa vessel. To view different portions of the deposit a physiciantypically moves a handle attached to a proximal end of the imagingcatheter along the vessel, for example, by pushing or pulling thecatheter.

Imaging using computer-assisted reconstruction algorithms enablesphysicians to view a representation of the patient's interiorintravascular structures in two or three dimensions (i.e., so-calledthree-dimensional or longitudinal view reconstruction). In thisconnection, image reconstruction algorithms typically employdata-averaging techniques which assume that the intravascular structurebetween an adjacent pair of data samples will simply be an average ofeach such data sample. Thus, the algorithms use graphical “fill in”techniques to depict a selected section of a patient's vascular systemunder investigation. Of course, if data samples are not sufficientlyclosely spaced, then lesions and/or other vessel abnormalities may infact remain undetected (i.e., since they might lie between a pair ofdata samples and thereby be “masked” by the image reconstructionalgorithms mentioned previously).

Even with the most skilled physician, it is practically impossible tomanually exercise sufficiently slow constant rate longitudinaltranslation of the ultrasound imaging device (which thereby provides fora precisely known separation distance between adjacent data samples). Inaddition, with manual translation, the physician must manipulate thetranslation device while observing the conventional two-dimensionalsectional images. This division of the physician's attention anddifficulty in providing a sufficiently slow constant translation ratecan result in some diagnostic information being missed. To minimize therisk that diagnostic information is missed, it is necessary to lengthenthe imaging scan time which may be stressful to the patient. Similarly,it is difficult for physicians to manually control the translationalrate of atherectomy catheters and other interventional devices that arelongitudinally advanced and retracted through blood vessel and otherbody lumens.

U.S. Pat. No. 5,485,486 discloses an ultrasound imaging transducer whichis capable of being translated longitudinally within a section of apatient's vascular system at a precise constant rate through the use ofa longitudinal translation assembly. The longitudinal translationassembly moves the entire rotary drive assembly to provide the desiredlongitudinal movement of the transducer. Such an ability enables aseries of precisely separated data samples to be obtained therebyminimizing (if not eliminating) distorted and/or inaccuratereconstructions of the ultrasonically scanned vessel section (i.e.,since a greater number of more closely spaced data samples can reliablybe obtained). Also, such an assembly can be operated in a “hands-off”manner which allows the physician to devote his or her attentionentirely to the real-time images with the assurance that all sections ofthe vessel are displayed. While such a longitudinal translation assemblycan work well, it is relatively large, bulky and heavy; it is expensive;and it is cumbersome to set up, in part because the rotary drive andlongitudinal translation assemblies are wrapped in separate steriledrapes or barriers (plastic bags) for sterility.

One of the disadvantages with some conventional pullback systems isseparate modules are used to provide the rotational and translationalmovement. These modules require the use of sterile barriers about each.Also, some prior art pullback systems lack the capability to permit theuser to manually translate the catheter core to preposition theoperative element along the distal end of the catheter core.

SUMMARY OF THE INVENTION

The present invention is directed to a driveable catheter system whichrequires only one sterile drape to be used about a catheter drive unit.The catheter and the pull-back sled preferably include no electricaldevices, such as motors, wires, batteries or electrical or electroniccomponents, and can be made to be disposable after a single use. Theinvention is designed so that user set up and translational movement issimplified. Manual translational movement of the catheter core, with theoperative element typically at is distal end, is easy andstraightforward. The invention preferably provides translationdisplacement information on displays carried by both the catheter driveunit and the control unit. The catheter drive unit and the control unitare preferably coupled in a manner to permit two-way communicationbetween the units thus permitting control signal inputs from the controlunit as well as the catheter drive unit itself.

The driveable catheter system includes a driveable catheter assemblyhaving a catheter drive unit movably mounted to a catheter drive sled. Acatheter extends from the catheter drive unit. Typically the catheterincludes an outer sheath, the proximal end of which if fixed in place bythe sled, and a catheter core, which is translatable and rotatablewithin the catheter sheath by the catheter drive unit. A control unit isspaced apart from the catheter drive unit also and preferably providespower for the catheter drive unit. The control unit preferably providesinputs to and receives information from the catheter drive unit.

The sled preferably includes a base having a drive track and drive unitadapter configured for removably coupling the catheter drive unit to thesled base. The sled also preferably includes a sled drive train, one endof which has drive unit interface operably coupleable to the catheterdrive unit. The other end of the sled drive train is coupled to thedrive track. The drive unit interface preferably has a generally conicaldrive surface having a bag-piercing tip so that a sterile drapeenclosing the catheter drive unit is automatically effectively piercedat the drive unit interface when the catheter drive unit is mounted tothe drive unit adapter.

The catheter drive unit preferably includes a housing, a catheter corerotator within the housing and drive unit translator within the housing.The drive unit translator preferably includes a translator drive motor,a translator drive train operably coupling the translator drive motor toa translator drive output. The translator drive output is engageablewith the preferably generally conical drive unit interface. Thetranslator drive train preferably includes a user operable clutch forselectively decoupling the translator drive motor from the translatordrive output. A translation displacement sensor is preferably locatedalong the translator drive train between the clutch and the translatordrive output so that actuating the clutch and manually moving thecatheter drive unit along the sled continues to provide accuratetranslational location information for the user.

Translation displacement information is preferably provided on a displaymounted to the catheter drive unit as well as on a display of thecontrol unit. The catheter drive unit preferably includes a displayreset button, a rotator drive ON/OFF button, and a translator driveON/OFF button. The control unit preferably provides for rotator driveon/off input, translator drive on/off input, rotation speed input andtranslation speed input. The catheter unit drive and the control unitare coupled through a two-way communication link which permits controlinformation to be provided to the catheter drive unit from the catheterdrive unit and from the control unit; appropriate communication linesare used to permit operational information and data to be provided bythe catheter drive unit to the control unit.

Other features and advantages of the invention will appear from thefollowing description in which the preferred embodiment has been setforth in detail in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an overall system schematic diagram of a driveable cathetersystem made according to the invention;

FIG. 1A is a simplified schematic representation of various componentsrelating to translation of the catheter core of FIG. 1;

FIG. 1B is a simplified schematic diagram of rotary drive components ofthe catheter drive unit of FIG. 1;

FIG. 2 is a perspective view of the driveable catheter assembly of FIG.1 including the catheter drive unit, the catheter drive sled and thecatheter;

FIG. 3 is a perspective view the catheter drive sled of FIG. 2;

FIG. 4 is a schematic illustration of the translational drive componentsof the catheter drive unit and sled of FIG. 1;

FIG. 4A is a simplified side view of the rolling support assembly forthe adapter of FIG. 3;

FIG. 5 is an enlarged side view of the drive unit interface of FIGS. 3and 4;

FIG. 5A is a simplified, exploded view of that portion of the sled drivetrain of FIG. 4 from the pinion gear to the drive unit interface; and

FIG. 6 is an enlarge partial top view illustrating the serrated natureof the conical drive surface of the drive unit interface of FIG. 5.

DESCRIPTION OF THE SPECIFIC EMBODIMENTS

FIG. 1 schematically illustrates a driveable catheter system 2 madeaccording to the invention. System 2 includes broadly a driveablecatheter assembly 4 operably coupled to a control unit 6 through atwo-way data and communication link 8. One such two-way communicationlink includes an RS232 communication link which permits information anddata from catheter assembly 4 to be directed to control unit 6 andpermits instructions and control signals to be provided to driveablecatheter assembly 4 from control unit 6.

Control unit 6 includes a display monitor 10 providing display oftranslation displacement information as well as other information.Control unit 6 also includes a control panel 12 which may include, forexample, an alphanumeric keyboard, dedicated input buttons or acombination thereof. Other type of inputs including voice command inputor a touch screen type of input can also be provided by control unit 6.In particular, control panel 12 provides for rotator drive on/off input14, translator drive on/off input 16, rotation speed input 18 andtranslation speed input 20.

Driveable catheter assembly 4 includes broadly a catheter drive unit 22,a catheter 24 mounted to and extending from unit 22, and a catheterdrive sled 26 engaging unit 22 and catheter 24. Catheter 24 includes acatheter core 34, with an operative element 32 (typically an ultrasonictransducer) at its distal end, housed within a catheter sheath 36.Catheter drive unit 22 includes a housing 28 to which an LCD translationdisplacement display 30 is mounted. Display 30 provides the user withtranslation displacement information relating to the translational (thatis, longitudinal or axial) position of operative element 32. Cathetercore 34 is rotatable and translatable (longitudinally slidable) withinsheath 36 of catheter 24. A display reset button 38, used to resettranslation displacement display 30 back to zero, is carried by housing28. A rotator drive ON/OFF button 40 and translator drive ON/OFF button42 are also carried by housing 28. This permits the user to start andstop both rotary and translational movement of catheter core 34 fromboth control unit 6 and catheter drive unit 22. FIG. 1A illustrates, inschematic form, various components relating to the translation ofcatheter core 34 coupled to a translator microcontroller unit 43, unit43 being located within drive unit 22.

Turning now also to FIGS. 2 and 3, the components of driveable catheterassembly 4 will be discussed. Catheter drive sled 26 includes a sledbody 44 having an upwardly extending, generally U-shaped nose portion46. Nose portion 46 includes a sheath-engaging clip 48 used to anchorthe proximal end 50 of sheath 36 to sled body 44. Sheath 36 includes ahub 49 which secures a telescoping portion 51 of sheath 36 to housing 28of unit 22. Telescoping portion 51 has a smaller diameter and slideswithin proximal end 50 of sheath 36.

The proximal end 52 of catheter core 34 is connected to and is rotatedby a rotator drive motor 54, see FIG. 1B, carried within housing 28.Rotator drive motor 54 is fixed relative to housing 28 so that thetranslational movement of housing 28 causes corresponding translationalmovement of catheter core 34 within sheath 36 thus moving the operativeelement 32 towards and away from the distal end 56 of sheath 36.

FIG. 4 schematically illustrates the translational drive components ofcatheter drive unit 22 and sled 26. Sled 26 includes a sled drive train58. Drive train 58 includes a rack gear 60; rack gear 60 defines a drivetrack 61 adjacent to and below a longitudinal slot 62 formed in sledbody 44. See FIG. 3. Catheter drive sled 26 also includes a cup-likedrive unit adapter 64 including a generally flat base 66 and anupstanding side wall 68. Side wall 68 includes a latch 70 used toautomatically secure catheter drive unit 22 to catheter drive sled 26when unit 22 is fully mounted to sled 26. To remove catheter drive unit22 from sled 26, the user must manually disengage latch 70 from housing28 of unit 22.

Adapter 64 is mounted for longitudinal movement along sled body 44 by anadapter rolling support assembly 71 as shown in FIG. 4A. Assembly 71includes a keel 72 fastened to and extending downwardly from base 66 ofadapter 64. Keel 72 is relatively flat and thin to pass through a keelslot 73, seen also in FIG. 3, formed in sled body 44 parallel to slot62. Adapter 64 is supported on sled body 44 by wheels 74. Keel 72 issecured to sled body 44 by a keel clip 75. Clip 75 has a pair ofinwardly extending lips 76 which engage spring arms 69 of keel 72. Keel72 and clip 75 have opposed V-shaped recesses 67 which capture an axle65 therebetween. The axle has a support wheel 63 on either end which lienear keel 72 and clip 75 and rest against the inside wall 59 of sledbody 44 on either side of slot 73.

Sled drive train 58 includes a pinion gear 78 mounted to the lower endof a two-part, extendable drive shaft 80. See FIG. 5A. The upper end 79,see FIG. 5, of shaft 80 supports a drive unit interface 82 mountedthereon. Shaft 80 also includes an internal compression spring 81 whichbiases interface 82 upwardly; the upward movement of upper end 79 islimited by the engagement of a snap finger 83 of upper end 79 with anappropriately positioned surface 85 of lower end 77. Drive unitinterface 82 is shown in more detail in FIGS. 5 and 6. Interface 82includes a serrated, generally conical drive surface 84 and a steriledrape-piercing tip 86.

FIG. 4 also illustrates, in simplified form, a translator drive train 88extending from a translator drive motor 90 to a translator drive output92. Translator drive output 92 has a conical drive surface 94 sized forcomplementary mating engagement with conical surface 84 of drive unitinterface 82. Motor 90 is coupled to a gear box 96 which drives a pairof pinion gears 98, 100.

Pinion gear 100 drives output 92 through a shaft 102. A clutch 104 ispositioned along shaft 102 for the purposes to be discussed below.Clutch 104 is operated by a manual clutch lever 106; actuation of manualclutch lever 106 opens clutch 104 and causes a clutch switch 108 to openwhich turns off translator drive motor 90. When clutch 104 isdisengaged, catheter drive unit 22 can be moved along drive track 61while maintaining engagement of interface 82 and drive output 92. Thetranslational position of catheter drive unit 22 (and more importantlyof operative element 32) is provided by a translation displacementsensor 110 positioned between clutch 104 and output 92. Positioningsensor 110 between clutch 104 and output 92 ensures that translationdisplacement information is provided to display 30 and display monitor10 regardless whether drive unit 22 has been moved by translator drivemotor 90 or manually after disengagement of clutch 104.

In use, a catheter drive unit 22 and an appropriate catheter 24 arechosen. Catheter drive unit 22, which is preferably reusable, willtypically be provided within a sterile bag or other sterile drape 112illustrated in dashed lines in FIG. 1. Sterile bag 112 is a flexible,drapeable material, typically 2 mil polypropylene, as is conventional.Appropriate connections with two-way data and communication link 8 aremade by a cable passing out of bag 112. Also, the hub 49 of catheter 24is mounted to catheter drive unit 22 by passing through a hole in bag112. (Sterile bag 112 is not shown in FIG. 2 for clarity ofillustration.) Assembly 4 is then mounted to sled 26 as shown in FIG. 2.Catheter 24 and sled 26 are each provided in a sterile condition. Driveunit interface 82 and output 92 engage one another with the bag-piercingtip 86 of conical interface 82 effectively piercing bag 112. Byeffectively piercing it is meant that drive unit interface 82 canactually pierce and create a hole in the bag, or the bag can be capturedbetween surfaces 84 and 94 (with or without a partial hole); in eithercase spring 81 creates sufficient force to create the desired mechanicalengagement between elements 82 and 92.

The proper mechanical engagement is maintained by engagement of latch 70with housing 28. The proper engagement is also aided by verticallyspring loading one or both of interface 82 and output 92. In thepreferred embodiment, surfaces 84, 94 are generally straight-sidedconical surfaces. Other generally conical interfaces having convex orconcave surfaces may be used. Generally conical surfaces includesurfaces which are not truly conical but are shaped to help ensureproper registration of the elements and effective piercing of thesterility bag 112. Generally conical thus includes spherical surfaces,oval surfaces, stepped surfaces and other surface shapes which generallytaper inwardly and provide the desired registration and drive functions.

Mounting unit 22 to sled 26 also includes clipping proximal end 50 ofsheath 36 to clip 48 at nose portion 46 of sled body 44 whiletelescoping portion 51, extending from hub 49, is free to telescope intoand out of proximal end 50. There is a sliding seal between end 50 andportion 51 to prevent contamination of catheter core 34. Translationalmovement of unit 22 along drive track 61 causes translation of cathetercore 34 but not of sheath 36; this causes the back and forth movement ofoperative element 32 at the distal end of catheter core 34 relative todistal end 56 of sheath 36.

Once unit 22 and sled 26 are properly secured to one another, clutchlever 106 can be moved to permit the user to properly locate unit 22along drive track 61. At this time display reset button 38 can bepressed to zero-out the translation displacement information at displays10, 30.

Distal end 56 of catheter 24 is positioned to an appropriate locationwithin the patient. Rotational and translational speeds are determinedand programmed at inputs 18, 20. Instead of inputting separateparameters, control unit 6 could be set up so that, if desired, once aprocedure is chosen, the procedure dictates, or suggests, the variousoperational parameters to be used.

Mounting assembly 4 to sled 26 also causes magnetic switch 116 to beactuated, typically closed, by the presence of a magnet 118 within driveunit adapter 64. See FIG. 1. In lieu of a magnetic switch, other typesof proximity switches could be used. In addition, magnetic switch 116could be replaced by a switch which would automatically be actuated onlywhen assembly 4 is fully mounted to sled 26. For example, a switch couldbe within housing 28 of unit 22 and actuated when latch 70 engageshousing 28. With magnetic switch off, that is with catheter drive unit22 not mounted to sled 26, display 30, sensor 110 and motor 90 are alloff. Once unit 22 is mounted to sled 26, display 30 and sensor 110 areturned on while motor 90 remains off. Rotary drive motor 54 is actuatedby using button 40 or input 14 which causes catheter core 34, and thusoperative element 32, to rotate. Upon pressing of translator driveON/OFF button 42 or instituting translational movement throughtranslator drive on/off input 16, motor 90 is turned on and the changingposition of operative element 32 is indicated at displays 10, 30. If theuser actuates manual clutch lever 106, this not only disconnects motor90 from output 92, it actuates switch 108 which also causes motor 90 toturn off.

The invention is typically used in a pullback mode. If desired, theinvention could be used to push operative element 32 towards distal end56 of sheath 36. To prevent injury to the patient or damage to the unit,motor 90 will be turned off when catheter drive unit 22 reaches the endof travel along drive track 61 as sensed by a current sensor monitoringthe current to motor 90. Motor 90 will also be automatically turned offif an obstruction is sensed, the obstruction preventing or hinderingmovement of unit 22 along drive track 61.

Modification and variation can be made to the enclosed embodimentwithout departing from the subject of the invention as defined in thefollowing claims. For example, according to certain aspects of theinvention sled 26 could include a battery to power motor 90; in thiscase interface 82 and output 92 could include both mechanical andelectrical connections or separate electrical connectors could beincluded with unit 22 and sled 26. Sled 26 could be made of sterilizablematerials so that the sled could be used more than once by users havingthe appropriate sterilization facilities.

Any and all patents, patent applications and publications referred toabove are incorporated by reference.

1. A catheter drive sled, for use with a catheter drive unit, the sledcomprising: a sled base comprising a drive track; a drive unit adaptermovably mounted to the sled base for movement along the drive track, thedrive unit adapter configured for removably mounting a catheter driveunit to the sled base; a sled drive train comprising a drive unitinterface operably coupleable to the catheter drive unit and a drivetrack interface operably coupled to the drive track; and the drive unitinterface comprising a drive surface that is adapted to pierce a drapedisposed about the catheter drive unit when the catheter drive unit ismounted to the drive unit adapter.
 2. The catheter drive sled accordingto claim 1 wherein the sled base comprises a raised nose portion.
 3. Thecatheter drive sled according to claim 2 wherein the nose portioncomprises a catheter sheath engagement member.
 4. The catheter drivesled according to claim 1 wherein the drive track comprises a rackhaving a plurality of teeth.
 5. The catheter drive sled according toclaim 1 wherein the sled base comprises a drive track guide and thedrive unit adapter comprises a guide element which engages with, isguided by and moves along the drive track guide.
 6. The catheter drivesled according to claim 5 wherein the guide element comprises guiderollers.
 7. The catheter drive sled according to claim 1 wherein thedrive surface is generally conical and extends outwardly away from thesled base and inwardly to a drape-piercing tip.
 8. The catheter drivesled according to claim 1 wherein the catheter drive sled is a singleuse, disposable sled.
 9. The catheter drive sled according to claim 8wherein the catheter drive sled is free from any electrical device. 10.A catheter drive unit, removably mountable to a catheter drive module,comprising: a housing; a catheter core rotator within the housing; adrive unit translator within the housing, the drive unit translatorcomprising: a translator drive motor; a translator drive output; and atranslator drive train operably coupling the translator drive motor andthe translator drive output, wherein the translator drive train isconfigured to selectively decouple the translator motor from thetranslator drive output.
 11. The catheter drive unit according to claim10 further comprising a translation displacement sensor located alongthe translator drive train between a clutch and the translator driveoutput, and a translator drive ON/OFF button operably coupled to thedrive unit translator, wherein the translator drive ON/OFF button ismounted to the housing, and further comprising a clutch lever to operatethe clutch.
 12. The catheter drive unit according to claim 11 furthercomprising a rotator drive ON/OFF button operably coupled to thecatheter core rotator, wherein the rotator drive ON/OFF button ismounted to the housing.
 13. The catheter drive unit according to claim11 further comprising a translation displacement display mounted to thehousing and operably coupled to the translation displacement sensor. 14.The catheter drive unit according to claim 13 further comprising aposition reset button operably coupled to the translation displacementdisplay.
 15. The catheter drive unit according to claim 13 furthercomprising a position-sensitive switch, actuatable when the catheterdrive unit is mounted to and dismounted from a catheter drive module,operably coupled to the translator drive motor and the translationdisplacement display.
 16. The catheter drive unit according to claim 15wherein the position-sensitive switch comprises a magnetic switch. 17.The catheter drive unit according to claim 10 wherein the catheter driveunit is adapted to be housed within a pierceable sterile drape and thetranslator drive output comprises a generally conical drive surface. 18.The catheter drive unit according to claim 17 wherein the generallyconical drive surface defines a generally conical open region.
 19. Acatheter drive unit comprising: a housing; a catheter core rotatorcarried by the housing; a drive unit translator carried by the housing;and a translation displacement display mounted to the housing andoperably coupled to the drive unit translator, and wherein the driveunit translator comprises a drive train, the drive train comprising atranslation displacement sensor operably coupled to the translationdisplacement display, and further comprising a clutch and a clutch leverto operate the clutch.
 20. A driveable catheter system comprising: adriveable catheter assembly comprising a catheter drive unit that isadapted to be coupled to a catheter; the catheter comprising a cathetercore rotatable and translatable by the catheter drive unit; and acontrol unit spaced-apart from but operably coupled to the driveablecatheter assembly, said control unit comprising: a catheter drive unitpower supply; a display monitor for displaying translation displacementinformation; and a catheter drive unit controller that is configured tocontrol catheter control rotation and translation; and wherein: thecatheter drive unit comprises a catheter core rotator and a catheterdrive unit translator; the catheter drive unit and the control unit arecoupled by a two-way electrical communication link; the control unitcomprises a rotator drive on/off input operably coupled to the cathetercore rotator and a translator drive on/off input operably coupled to thecatheter drive unit translator; the catheter drive unit comprises arotator drive on/off input operably coupled to the catheter core rotatorand a translator drive on/off input operably coupled to the catheterdrive unit translator; the control unit comprises a control unittranslation displacement display; and the catheter drive unit comprisesa drive unit translation displacement display.
 21. A catheter systemaccording to claim 20 wherein the driveable catheter assembly comprisesa catheter drive sled, the catheter drive unit removably mountable tothe catheter drive sled for translational movement therealong.
 22. Acatheter system according to claim 21 wherein the catheter drive sled isa single use disposable unit free from any electrical device.
 23. Acatheter system according to claim 21 wherein: the catheter drive unitcomprises: a proximity switch, movable between OFF and ON positions,electrically coupling the catheter drive unit translator to the controlunit when in the ON position; and the catheter drive sled comprising aproximity switch actuator which interacts with and actuates theproximity switch to the ON position when the catheter drive unit ismounted to the catheter drive sled.
 24. A driveable catheter assemblycomprising: a catheter drive sled; a catheter drive unit removablymountable to the sled; a catheter comprising a rotatable andtranslatable catheter core operably coupled to and extending from thecatheter drive unit; the catheter drive unit comprising: a drive unittranslator operably coupled to the sled for selective translationalmovement of the catheter drive unit and catheter core therewith relativeto the sled; a catheter core rotator operably coupled to the cathetercore for selective rotation of the catheter core; and a proximity switchoperably coupled to at least one of the drive unit translator andcatheter core rotator, and wherein the sled comprises a proximity switchactuator which interacts with and actuates the proximity switch when thecatheter drive unit is mounted to the sled, wherein the proximity switchis a magnetic switch and the proximity switch actuator is a magnet, andfurther comprising a clutch and a clutch lever to operate the clutch.25. A driveable catheter system comprising: a driveable catheterassembly comprising a catheter drive unit, a catheter extending from thecatheter drive unit, and a catheter drive sled, the catheter drive unitremovably mountable to the catheter drive sled for translationalmovement therealong; the catheter drive unit comprising: a catheter corerotator drivingly coupled to the catheter; a catheter drive unittranslator drivingly coupled to the catheter drive sled; and a rotatordrive on/off input operably coupled to the catheter core rotator; and atranslator drive on/off input operably coupled to the catheter driveunit translator; and a drive unit translation displacement displayoperably coupled to the catheter drive unit translator; the cathetercomprising a catheter core rotatable by the catheter core rotator andtranslatable with the catheter drive unit by the catheter drive unittranslator; and a control unit spaced-apart from but operably coupled tothe driveable catheter assembly, said control unit comprising: a rotatordrive on/off input operably coupled to the catheter core rotator and atranslator drive on/off input operably coupled to the catheter driveunit translator; a control unit translation displacement displayoperably coupled to the catheter drive unit translator, wherein thedisplay is configured to display translation displacement information; acatheter drive unit power supply electrically coupled to the cathetercore rotator and the catheter drive unit translator; and a catheterdrive unit controller comprising a catheter core rotation speed inputand a catheter core translation speed input; wherein the catheter driveunit and the control unit are coupled by a two-way electricalcommunication link.
 26. A catheter system according to claim 25 wherein:the catheter drive unit comprises a proximity switch, movable betweenOFF and ON positions, electrically coupling the catheter drive unittranslator to the control unit when in the ON position; and the catheterdrive sled comprising a proximity switch actuator which interacts withand actuates the proximity switch to the ON position when the catheterdrive unit is mounted to the catheter drive sled.
 27. A catheter systemaccording to claim 26 wherein the proximity switch is a magnetic switchand the proximity switch actuator comprises a magnet.
 28. A method forsetting up a catheter drive system comprising: providing a catheterdrive unit with a catheter extending therefrom, the catheter comprisinga rotatable and translatable catheter core, the catheter drive unitcomprising a rotator drive motor rotationally coupled to the cathetercore, a translator drive motor, and a catheter core mounting thecatheter drive unit to a catheter drive sled, the catheter drive sledcomprising a drive unit interface configured for mating engagement withthe translator drive output; said mounting step comprising effectivelypiercing the drapeable barrier by the engagement of the translator driveoutput and the drive unit interface.
 29. The method according to claim28 wherein the mounting step is carried out with the drive unitinterface having a generally conical drive surface.
 30. The methodaccording to claim 29 wherein said mounting step is carried out with thegenerally conical drive surface comprising a barrier-piercing tip.
 31. Amethod for controlling the use of a driveable catheter assembly of thetype comprising a rotatable and translatable catheter core extendingfrom a catheter drive unit, comprising: providing a control unitphysically remote from but operably coupled to the catheter drive unit;and selectively controlling starting and stopping of rotational andtranslational movement of the catheter core from the catheter drive unitand from the control unit; and viewing translation displacementinformation from displays at the catheter drive unit and the controlunit.
 32. The method according to claim 31 further comprising resettingthe translation displacement information from the catheter drive unit.33. A method for setting up and using a catheter drive systemcomprising: selecting a catheter drive unit, a translator drive motor,and a catheter core drive train having a translator drive outputdrivingly coupling the translator drive motor and the translator driveoutput, the catheter drive unit being enclosed within a removabledrapeable barrier.
 34. The method according to claim 33 furthercomprising viewing translation displacement information from displays atthe catheter drive unit and the control unit.
 35. A catheter drive unit,removably mountable to a catheter drive module, comprising: a housing; acatheter core rotator within the housing that is configured to rotate acatheter core of a catheter; a drive unit translator comprising atranslation drive motor that is disposed within the housing and that isconfigured to translate the catheter core of the catheter; and atranslation displacement sensor that is configured to measure the amountof displacement of the catheter core; a translator drive output; and atranslator drive train operably coupling the translator drive motor andthe translator drive output, wherein the translator drive train isconfigured to selectively couple and decouple the translator motor fromthe translator drive output.
 36. The catheter drive unit according toclaim 35, wherein the translation displacement sensor is located alongthe translator drive train between a clutch and the translator driveoutput so that the translator displacement sensor will continuouslymeasure the amount of displacement of the catheter core regardless ofthe state of the translator drive train. drive train having a translatordrive output drivingly coupling the translator drive motor and thetranslator drive output, the catheter drive unit being enclosed within adrapeable barrier; mounting the catheter drive unit to a catheter drivesled, the catheter drive sled comprising a drive unit interfaceconfigured for mating engagement with the translator drive output; andsaid mounting step comprising effectively piercing the drapeable barrierby the engagement of the translator drive output and the drive unitinterface.